Elucidation of Electrode Reaction of EuCl3 in LiCl-KCl Eutectic Melts through CV Curve Analysis

The electrode reaction of Eu3+ in a LiCl-KCl eutectic melt has been re-examined using cyclic voltammetry (CV). In this work, for the first time, the kinetic details of a Eu3+/Eu2+ redox system have been completely elucidated, along with the thermodynamic property, through a curve fitting applied to experimental CV data, which were obtained in a wide scan rate range of 0.5 to 10 V/s. The simulated results showed an excellent fit to all experimental CV data simultaneously, even though the curve fittings were performed within a large dynamic range of initial transfer coefficient values, formal potentials, and standard rate constants. As a result, a proper formal potential, transfer coefficient, and standard rate constant for the Eu3+/Eu2+ redox system were successfully extracted using the CV curve fitting.